In my role as a graduate policy assistant with the Berkeley Food Institute (BFI), I’ve been a part of a team of researchers at UC Berkeley who launched an agrivoltaics project this fall. As part of this work, we hosted a workshop that surfaced many opportunities to research how to equitably co-locate solar arrays with agricultural production within California. I wanted to better understand how the community solar market can help advance innovations like agrivoltaics. To do that I interviewed experts in the field. 

What I learned is that the lack of a community solar market in California helps to explain why very few agrivoltaics projects have developed here relative to other states. 

What is Community Solar? 

“When you look at states that have some good examples of [agrivoltaics], they are states with mature community solar markets, like Massachusetts,” said Derek Chernow, western regional director of coalition for community solar access (CCSA). “This includes a compensation structure in place for community solar, which allows those farmers to have that certainty and make informed decisions.” 

Community solar refers to smaller scale developments, often 2-5 megawatts (MW), that are physically located close to communities that need the power. Such projects allow community members — including renters and institutions like schools and businesses who don’t own their roof — to opt-in to receive power from a portion of the solar array. Program participants then receive a credit on their utility bill that reflects the amount of energy generated by their share of the solar array. 

In this arrangement, a farm could host a community solar development while also receiving clean energy and a reduced utility bill.

This model is contrasted with utility scale solar developments, which are sometimes hundreds of MW in size and therefore require large amounts of land. A general rule of thumb assumes five acres per MW, based on information from a 2013 National Renewable Energy Laboratory (NREL) study. Technology has advanced since that report, but project footprints haven’t changed dramatically. 

“Community solar expands the set of landowners who could host a project,” said Austin Kinzer of American Farmland Trust. “There is a benefit in making solar projects more accessible to smaller landowners. This is about making the pie bigger within the solar market.” 

Benefits to the Local Community 

One aspect of community solar and storage development is the ‘local reliability area’, meaning subscribers who receive the power are in the vicinity of the power source. 

In cases where agrivoltaics and community solar combine, farmers can offer their neighboring communities the chance to receive clean energy, while lowering their electricity bill.

While it is possible that community solar can increase rural energy resilience, it is not a given. Grid dynamics and electrical engineering specifics dictate the flow of energy on a case by case basis. Solutions may go beyond community solar and enter into the domain of mini (or micro) grids. 

“Particularly in the context of public safety power shutoffs, [local] solar and storage could be immensely valuable to mitigate the impacts when a whole transmission line is shut down,” Kinzer said. “When considering reliability, though, it is important that projects get sited intentionally in areas that could benefit from increased generation and storage.” 

Pilot-testing Scale for Agivoltaics 

There are currently around 600 agrivoltaic projects in the country. Projects at the community solar scale have had more success getting off the ground. The NREL InSPIRE program tracks existing agrivoltaic projects in the United States, broken out between developments associated with animal grazing, crop production, and pollinator habitats. Most projects favor grazing and pollinator habitat, thus increasing the likelihood that crop agriculture is linked to agrivoltaic projects. 

According to InSPIRE, the vast majority (70% or 414 projects) of agrivoltaics projects in the country are community solar size (less than 5 MW), and 40 of those projects include cropland farming. In contrast, of the projects bigger than 5 MW, only three projects incorporate cropland agriculture.

“Starting with these smaller sites is a necessary step to enable crop agrivoltaics,” Kinzer stated. “There is so much geographic variability. We need localized sites to demonstrate what is possible for a specific region with specific crops and the challenge in California has been there is not a market for small and medium solar to get built.” 

Reduce Interconnection Challenges

The land requirement for utility-scale solar projects means they’re usually not built close to centers of energy demand. These larger scale projects must transmit their energy across long distances via high-voltage transmission networks. The power then connects to lower-voltage distribution lines to efficiently bring power to homes and businesses. The process of connecting a source of energy generation to the grid is referred to as ‘interconnection.’ 

In 2024, Lawrence Berkeley National Lab found that numerous projects representing a total of nearly 2,600 GW (there are 1000 MW in 1 GW) are waiting for connection in the long California interconnection queue. According to the Berkeley Lab’s report, “this growing backlog has become a major bottleneck for project development: proposed projects are mired in length and uncertain interconnection survey processes and most interconnection requests are ultimately canceled and withdrawn.”  

Reducing the interconnection challenges with community solar can increase the chances of a project making it out of the queue. For example, agrivoltaics kept within the 2-5 MW scale can help expedite the process and avoid the time and money lost to an unsuccessful interconnection survey. 

“One of the key benefits of community solar is that you are connecting at the distribution level, which makes it easier to interconnect,” said Kinzer.

Challenges for Community Solar in California 

Chief of Staff in Senator Ben Allen’s office, Tina Andolina, worked on California’s community solar bill, SB 43 in 2013 for former Senator Lois Wolk (D-Davis). For Andolina, the barrier to community solar comes down to whether subscribers are compensated at a retail versus wholesale rate for their power. When she originally worked on the 2013 bill, the idea was to compensate subscribers at the same retail rate provided to rooftop solar users. Before the bill passed, however, opponents voiced concerns and SB 43 was amended to compensate subscribers at the wholesale rate.

“If you reduce the subsidy, then the projects don’t pencil out,” Andolina said. “And, without penciling out, there has been no demand for this type of program.” With SB 43 on the books for twelve years, very few community solar projects have come online. 

This year, Assemblymember Christopher Ward introduced AB 1260 to try to address this. Chernow’s organization, CSSA, supported the bill alongside a diverse coalition. “AB 1260 outlines a path to a robust, sustainable community solar and storage program, utilizing the California Public Utility Commission’s (CPUC) Avoided Cost Calculator for valuing distributed energy resources [such as rooftop solar],” said Chernow. The bill did not make it out of appropriations this session. 

Andolina commented that if new legislation could have meaningfully changed the compensation structure, California would finally start to see more community scale solar projects come online. 

While there was nothing specific to agrivoltaics in AB 1260, addressing the current barriers to community solar could create the conditions for more pilot agrivoltaics projects. Further work will be necessary to advance agrivoltaics and community solar in California. 

“Community solar is a great step, but the lack of any acknowledgment or priority for agrivoltaics in AB 1260 [was] a missed opportunity for California farmers,” said Kinzer.